Foods that contain acrylamide are unlikely to cause breast cancer, according to new research involving 100,000 U.S. women.

Acrylamide is a chemical commonly found in French fries and coffee. Animal studies have previously linked it to cancer.

The preliminary results of the most recent study were presented at the 234th meeting of the American Chemical Society. Researchers said that when consumed at normal dietary levels, acrylamide does not appear to increase a woman’s risk of breast cancer.

“Although we do not rule out that very high levels of acrylamide could cause cancer, it appears that at the levels found in the diet, it is unlikely,” said study leader Lorelei Mucci, an epidemiologist at Channing Labs at Brigham and Women’s Hospital and Harvard School of Public Health in Boston, in a news release.

The highest levels of acrylamide are found in fried and baked products such as potato chips and other snack foods. Although classified as a probable human carcinogen on the basis of animal studies, there is currently no consensus on dietary acrylamide’s risks to human health, the study said.

In a previous study involving Swedish women, Mucci and colleagues found no association between dietary acrylamide and cancer risk.

In the new study, researchers followed a group of 100,000 nurses over 20 years (from 1980 to 2000) using periodic questionnaires about their dietary habits, including the type of foods eaten and their frequency of consumption.

The data was used to estimate daily acrylamide intake, while collecting information on the incidence of breast cancer among the women.

More than 3,000 cases of breast cancer were diagnosed in the study group, which is average for a group of 100,000 women. The incidence of breast cancer among women with high acrylamide intake was about the same as that among women with low intakes, indicating a lack of association between acrylamide intake and breast cancer, the researchers said.

Mucci and her associates are now studying a possible link between acrylamide and prostate cancer.